The present invention relates to a support with low material thickness for a synchronizing ring for gear synchronization with a conical friction contact surface, an outer sprocket and stops for coupling to the clutch.
Various types of supports are known for synchronizing rings; these differing mainly in the selection of material. As far as shape is concerned, the supports consist substantially of a ring-shaped body having a sprocket on its outer edge for positive locking to the corresponding moving wheel. Several, usually three, lugs or pockets, displaced by 120.degree., are provided on the surface of the ring-shaped part which act as stops for coupling the synchronizing ring to the clutch.
Synchronizing rings of this type are usually produced by a casting process, however, it has also been proposed to produce synchronizing rings by a punching and drawing process. For example, French Pat. No. 1,553,343 describes such a method where fist a hat-shaped object is produced by a deep-drawing method, the edge of which is provided with a sprocket in the subsequent process step and the bottom of which is removed. The last process step produces three recesses in the ring-shaped body, these recesses serving as stops for coupling to the gearshift sleeve. This synchronizing ring could not satisfy all the requirements qualitatively that could be fulfilled by a synchronizing ring produced by the casting method. Thus, for example, the transition from the ring-shaped part to the sprocket ring had a rounded portion on the inner surface which is undesirable because it cannot be utilized for the synchronization process. Also, when there is a tight fit, the recesses are disadvantageous for locking to the gear-shift sleeve because they also reduce the frictional contact.
The task of the present invention is to create a support for a synchronizing ring, which support can be introduced even when there is a tight fit and, in spite of this, it has maximum frictional contact on its conical friction surface.